Holding arm for record changer



March 12, 1963 w. J. KNOPFLE .El'AL 3,081,094

HOLDING ARM FOR RECORD CHANGER 1 Filed Nov. 25. 1960 2 Sheets-Sheet 1'Fig. 1

ATTORNEY j March 12, 1963 w. J. KNUPFLE EI'AL 330811994 HOLDING ARM FORRECORD CHANGER Filed Nov. 25, 1960 2 Sheets-Sheet. 2

WALTER JOSEPH KNWFTE HANS GERHARD HAGENAH ATTORNEY;

UnitedStates Patent Office 3,081,094 Patented Mars '12, 1963- U3,081,094 HOLDING ARM FOR RECORD CHANGER Walter Josef KniipfleandHansGerhard Hagenah, St; Georgen, Germany, assignors to- Perpetuum-Ebner,Fabrik fur Feinmechanik und Elektrotechnik Steidiner CoL, .KomwGesL, St.Georgen, Germany Filed Nov. 25,1960, Ser. No. 71,673 Claims priority,application Germany Nov'. 26, 1959 2Claims. (CL. 274 110- This inventionrelates to astabilizingarm for automatic record changers, andspecifically relates to. an arm which can be moved to its operative andinoperative positions with one simple movement by the operator thereof.

An important objective of this invention is toprovide a stabilizingarmwhich has an extension which follows a grooved surface so that a precisemovement is automatically transmitted to the arm, even though theactuating movement given to the arm itself is imprecise.

A further objective of this invention is to provide a spring-biasedlocking member along the grooved surface so that the arm will remain inan inoperative position until actuated by an operator.

These and other objectives and advantages of this invention will beapparent from the following description and claims wherein theconstruction, arrangement and cooperation of the parts of the apparatusare set forth.

In the drawings:

FIG. 1 is a side view of an automatic record changer device of the typeto which the stabilizing arm of this invention is adapted to be used;

FIG. 2 is a plan view thereof; and

FIG. 3 is a bottom perspective of the stabilizing arm showing itscontrol mechanism.

Referring now more specifically to the drawings Where like numeralsindicate like parts, the numeral indicates a record player of a typeplaying a succession of disc records. The mechanism of the record playerresponsible for the starting, the back and forth movement of the tonearm; in other words, the changing mechanism, is not dis-t closed in thedrawings because the invention defined herein may be used withconventional types of equipment.

The record player is comprised of frame 11 having a circular depression11a which receives the circular turntable 12. The turntable has adownwardly extending annular flange 12a which extends into thedepression 11a. A mounting plate 14 on the underside of the frame 11 issupported thereto by the spacing pins 13 and 13'. It is to this mountingplate 14 that the various parts for the changing mechanism are secured.

An annular bearing 15 journaled in the plate 14 receives a hollow,inverted cone 16. vThishollow cone 16 serves as a resting cone for theturntable 12. Referring to FIG. 1, it can be seen that the cone isequipped with a ridge 17 which supports the turntable 12 and a ridge 17awhich lies adjacent to the upper annular surface 15a of the bearing 15.Any suitable means for rotating the turntable may be used such as a gearwheel associated with the cone 16 or hearing 15. For instance, thejournal 15 may be made with gear teeth which could mate with a largergear wheel attached to the record changer operating motor.

A spindle 18 is secured to cone 17 by insertion into the annular channel16. The spindle 18 is of a type having an offset portion 18a which formsa supporting ledge 18b for supporting a stack of records 19. After thebottom record 19a has been played, a slight shifting in the ledge causesthe next bottom record to drop onto the turntable While retaining theothers on the ledge 18b. This action is conventional and is well knownto the art.

A tone arm 20 is fastened to the frame 11 by way of an upright standard21. The tone arm is able to be swung 2 about a vertical axis 23,andabout "the horizontal axis 24. Also spaced on frame 11'is an uprightbracket 25 in which a vertical spindle 26 is rotatably supported. Thespindle 26' may be swung back'and forth aswell as movedup and down. Astabilizing or holding arm 26 is fastened to the upper end of spindle26. The holding arm 27 is equipped along its underside with small,resilient record-engaging pads 27b which will not scratch or marthe toprecords surface. The arm 27 aids in maintaining'the record stack 19 in ahorizontal, stabilized position while theyare supported on ledge 18a.Since stabilizing isfbestaccorn plijsh'ed .by pressure on' severalpoints; spaced from the ledge, the engaging end 2711' of the holdingarmis -semi-. circular in configuration.

The lower end of spindle 26 is equipped with a h'orizo'rn tal rod or camfollower 30; Between this rod 34); and the underside of mounting plate.11 is a coil spring 31Which biases the stabilizingarm 27 downwardlyalong-an axis A. This insures continuous stabilization whenever a recordleaves the bottom of record stack 19.

Extending downwardly from the underside of mounting plate 11, in thevicinity of the outer end of rod 30, is a backdrop or cylindrical flange32 fastened to the underside of the frame 11 through a triangularmounting member 32a. The backdrop 32 is curvilinearly formed and theinner radial edge thereof is concentric to the axis of shaft or spindle26.- The backdrop is positioned at a dis tance so that the free end ofthe arm 30 partly penetrates the thickness of the backdrop.

The surface of the backdrop is formed with a generally triangular grooveor cam surface 3211. This cam surface receives t1 e arm or cam follower30. Therefore, it can be seen that shaft 26 which supports the holdingarm 27 can only be rotated and moved up and down as the position of thearm 39 in the groove 32b permits.

The groove 32b is comprised of three separate components; a groove 32b1runs parallel to the axis of spindle 26, a groove 32b2 runs horizontaland parallel with the mounting frame 11, and the groove 32123 runs fromthe lower end of groove 32b2 on an arc to one end of the horizontalgroove 32111.

Groove 32121 extends slightly beyond the groove 32b3 so as to form asmall ridge or ledge 320. The arm 30 rests on this ridge while thestabilizing member 27 is swung outwardly (clockwise from the positionshown in FIG. 2) when in its inoperative position.

A one-way gate 34 is pivotally secured on a pin 34 in the vicinity ofthe ledge 32c and permits the arm 30 to move only upwardly into thegroove 32b1. The gate is biased clockwise as viewed in FIG. 3 against 2.lug 37. Therefore, as seen best in FIG. 3, the arm 30 may move upwardlyinto 32b1 but may not return downwardly through 32123 after it haspassed gate 34. Upon moving the stabilizer 27 to its operative orstack-engaging position, the arm 3% travels along groove 32111 until itreaches groove 32b2. At this point, it starts to move downwardly (withthe arm 27) under the action of gravity and spring 31 until thestabilizing arm 27 engages the top record of stack 19. After the stack19 has been played, the arm 3th will be at the lower end of groove32112. In some record players there is a limit switch at this pointwhich will turn off the machine.

At this point, an operator need only move the arm 27 clockwise (asviewed in FIG. 2) and the arm will automatically reach its outer raisedposition above gate 37. Therefore, it is not necessary for the operatorto first rotate, then raise, or vice versa. The operator need only pushthe arm in the proper direction and it automatically assumes its correctposition.

In a general manner, while we have, in the above description, disclosedwhat we deem to be practical and eificient embodiments of our invention,it should be well understood that we do not wish to be limited thereto,as

there might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

We claim:

1. In stabilizing apparatus for record changers of the type wherein aplurality of records are stacked on a spindle ledge to be successivelydropped down upon a turntable, the combination including, a frame, avertical support shaft journalled in said frame for rotational and axialmovement, a stabilizing arm extending horizontally from the upper end ofsaid shaft for engaging with the top surface of said stack of records, abackdrop member extending downwardly from said frame, said backdropbeing provided with a cam track, said track including a first verticalportion, a second horizontal portion and a third angularly relatedportion, the ends of said track 7 portions being joined to provide agenerally triangular 20 continuous cam track, a cam follower extendinghorizontally from the lower end of said shaft and in operativeengagement with said triangular cam track, at least said secondhorizontal portion of said cam track comprising an arcu'ately arrangedgroove into which the free end of said follower is received to preventvertical movement of said stabilizing arm in either direction, andone-way latch means positioned at the intersection of said second andthird cam tracks to prevent movement of the cam follower from the secondportion of the cam track into the third portion without first movingthrough the first portion.

2. The invention as defined in claim 1, wherein a coil spring encirclessaid vertical shaft, said spring being connected to urge said shaft in adownward direction.

References Cited-in the-file of this patent I UNITED STATES PATENTS

1. IN STABILIZING APPARATUS FOR RECORD CHANGERS OF THE TYPE WHEREIN APLURALITY OF RECORDS ARE STACKED ON A SPINDLE LEDGE TO BE SUCCESSIVELYDROPPED DOWN UPON A TURNTABLE, THE COMBINATION INCLUDING, A FRAME, AVERTICAL SUPPORT SHAFT JOURNALLED IN SAID FRAME FOR ROTATIONAL AND AXIALMOVEMENT, A STABILIZING ARM EXTENDING HORIZONTALLY FROM THE UPPER END OFSAID SHAFT FOR ENGAGING WITH THE TOP SURFACE OF SAID STACK OF RECORDS, ABACKDROP MEMBER EXTENDING DOWNWARDLY FROM SAID FRAME, SAID BACKDROPBEING PROVIDED WITH A CAM TRACK, SAID TRACK INCLUDING A FIRST VERTICALPORTION, A SECOND HORIZONTAL PORTION AND A THIRD ANGULARLY RELATEDPORTION, THE ENDS OF SAID TRACK PORTIONS BEING JOINED TO PROVIDE AGENERALLY TRIANGULAR